This invention relates to non-combustible nicotine dispensing devices designed to reduce or eliminate the disadvantages associated with conventional smoking habits.
Nicotine is a toxic liquid alkaloid having the formula C.sub.5 H.sub.4 NC.sub.4 H.sub.7 NCH.sub.3. When nicotine is obtained from tobacco, as by chewing, sniffing or smoking the substance, the amount of nicotine absorbed into the body generally does not build up to a harmful dose, but produces certain pleasurable effects, frequently leading to habitual use.
One of the most popular versions of nicotine use involves the smoking of cigarettes. When the tobacco in a conventional cigareete is ignited, the combustion of the processed tobacco leaves within the cigarette causes the release of vaporous nicotine, which is drawn through the cigarette and into the user's mouth and lungs when the user sucks or inhales air through the cigarette.
The relative mildness of a cigarette, as compared to a pipe or cigar, permits a user to draw the smoke from the burning cigarette directly into the lungs. Nicotine vapors in the cigarette smoke are rapidly assimilated into the bloodstream of the user from the lungs, so that cigarette smoking provides a method by which a user may very quickly feel the effects of the nicotine.
Although nicotine can be readily introduced into the body through cigarette smoking, the combustion of the tobacco, with the consequent elevated temperatures required in this process, unfortunately results in a number of undesirable consequences associated with smoking combustible cigarettes. Of primary concern are the serious health hazards thought by many to result from smoking combustible cigarettes. The nicotine content of a cigarette is not believed to cause any serious adverse long-term health effects on the human body. Other components, however, are present in tobacco smoke which are thought by many to be harmful. Some of these other components, for example, appear to be carcinogenic.
Furthermore, the smoking of combustible cigarettes may pose a significant fire hazard. Many first which have occurred both within buildings or in natural environments have been attributed to carelessly discarded burning cigarettes. In addition, substantial economic losses may be attributed to smoking, including, for example, significant damage to business and personal property resulting from burns in clothing, carpeting, furniture, etc. caused by stray ashes from cigarettes. Cigarette smoking has also become increasingly objectionable because of the discomfort it may cause to non-smokers who are exposed to the smoke and odor produced by practitioners of the smoking habit.
Because of these undesirable side effects of conventional cigarette smoking, attempts have been made from time to time to provide acceptable substitutes. Such substitutes for combustible cigarette smoking eliminate or ameliorate some or all of the adverse consequences mentioned above. Tobacco concentrates, for example, have been processed into a tablet form which may be sucked or chewed, the nicotine being absorbed into the user's body through the lining of the mouth and digestive system. Such a tablet, of course, does not provide the user with the feel of a cigarette held between the lips.
Furthermore, a tablet-type smoking substitute cannot provide the user with an opportunity to draw air and vapors into the mouth nor inhale the air and vapors into the lungs, these actions being a part of the convetional smoking habit. These actions or activities constitute an important aspect of the psychological and physiological affinities which a smoker acquires for the habit. Without an effective substitute for such smoking activities, a smoking substitute is less likely to satisfy the user and may thus result in a return to combustible cigarette smoking.
An important step forward in the development of a smoking substitute is described in U.S. Pat. No. 4,284,089 to Ray, assiged to the assignee of the present invention and incorporated by reference herein. In this patent a smokeless device for dispensing nicotine is described which may take the appearance of a conventional smoking item, such as a cigarette. Moreover, the device disclosed in the patent enables nicotine to be dispensed in response to users actions that closely simulates conventional smoking activity.
In an illustrated embodiment, the Ray patent discloses a device having the general configuration of a cigarette. However, the exterior of the device defines a gas flow passageway with a flow restriction. The flow restriction is defined by an absorbent material carrying a nicotine solution on the material. In response to the fluid velocity developed at the restriction, nicotine is vaporized from the absorbent material and inhaled by the user. As a result, the user attains a nicotine induced sensation quite similar to that obtained by smoking conventional cigarettes.
While it may be safely posited that the Ray patent represents a pioneering advance in the art, the inventors of the present invention have appreciated that it would be desirable to optimize the performance of a device of the general type disclosed in the Ray patent. In one aspect, for example, the present inventors have appreciated that it would be highly desirable to increase the amount of nicotine that is vaporized in response to a given puff on such a device.
It is also very important in a nicotine dispenser of this kind to effeciently vaporize the nicotine. Liquid nicotine has an extremely bitter, almost caustic taste. Thus, it is important to dispense the nicotine in a fashion which encourages controlled vaporization while preventing inadvertent suction of unvaporized droplets, even those of very small size.
Finally, the present invention have appreciated that the above described objetives are most advantageously achieved with a device having a "draw" similar to that of a conventional smoking device, such as a cigarette. It is believed that users may rapidly become dissatisfied with a smoking substitute that requires too little or, more particularly, too much inhalation effort for the sensation achieved. Similarly if the device dispenses too high a nicotine dosage with each puff, the user may receive more nicotine than desired and may be forced to change smoking habits. Either of these alternatives is undesirable in that the user will be less willing to substitute the smokeless substitute if the "familiar feeling" is compromised or if the substitute is somehow less pleasurable.
In addition to U.S. Pat. No. 4,284,089 mentioned earlier herein, others have described nicotine dispensing devices. U.S. Pat. No. 4,393,884, for example, describes a demand inhaler holding a reservoir of pressurized nicotine and having a complicated mechanical system, all encased in a tube for oral nicotine input. U.S. Pat. No. 2,860,638 describes a tubular device for oral inhalation of substances such as nicotine. This device may contain filler material such as cotton or mineral matter in which substances such as nicotine may be absorbed.
U.S. Pat. No. 3,280,823 describes a tobacco smoke filter comprising an ion-exchange resin containing nicotine for nicotine enrichment of gases inhaled therethrough. U.S. Pat. No. 3,584,630 describes a filter section comprising nicotine weakly absorbed on carbon black for nicotine enrichment of inhaled gases.
U.S. Pat. No. 4,083,372 describes a cigarette-simulating inhaler with a fibrous wick of material such as cellulose acetate or cotton fibers and a puncturable capsule of flavorant for release into the wick prior to inhalation of air therethrough.